I am happy to say the boiler is now working perfectly, have run 3 full baths and filled the sink for 5 minutes all were very hot and water temp was constant.
I have to say a great thanks to both Tony and Gareth for pointing me in
the right direction.
The DHW temp control had been moved...
I have a problem with a ravenheat rsf 84et, firstly the diverter valve was
leaking and needed to be replaced. A genuine one was sourced and replaced (including microswitch). Now the hot water is cycling hot then cold
every 20 s or so, also the water in the boiler seems to be boiling so i...